Starting systems



June 1960 P. L. SCHNEIDER ETAL 2,939,964

STARTING SYSTEMS Filed March 6, 1957 INVENTORS P401. L. SCHNEIDER BRTHUR Wham/mm ATTORNEY STARTING SYSTEMS Paul L. Schneider and Arthur W.Alexander, Anderson,

Ind., assignors to General Motors Corporation, Detroit, Mich., acorporation of Delaware Filed Mar. 6, 1957, Ser. No. 644,350

1 Claim. (Cl. 290-38) This invention relates to starting systems forinternal combustion engines and is more particularly concerned withstarting systems wherein the control of the actuation of the starter isaccomplished without human assistance.

Internal combustion engines which are used as emergency sources of powerfrequently are equipped with automatic starting systems. That is, theenergization of the starting system for the engine is initiatedautomatically in response to an outside event without human assistanceor attention. Further, these engines frequently are installed at someremote location. Therefore, if these engines are to fulfill theirexpected function, the starting systems for these engines must bevirtually fool-proof. While the starting systems which will be hereindescribed may be used to supply cranking torque to other than stationaryemergency power equipment, it is particularly suited to installationswherein the engine is started and operated without human attention.

On a typical starting system for an internal combustion engine, such asshown in US. Patent 2,716,895, the starting motor is provided with astarter drive. This starter drive includes a pinion gear which is movedinto meshing engagement with the ring gear on the engine to be started.The starting motor when energized supplies the cranking torque to causethe engine to become selfoperative. The movement of the starter drivepinion gear into meshing engagement with the ring gear is accomplishedby a solenoid which not only moves the pinion gear into engagement butalso closes the circuit to the starting motor. On occasion, it has beenfound that tooth abutment will occur between the pinion and the ringgear of the engine when the pinion gear is moved into engaging position.When this tooth end abutment occurs, the teeth of the pinion gear abutthe end of the teeth of the ring gear and are prevented from passinginto the spaces between the teeth of the ring gear. When this occurs,the solenoid of the starting system will continue to be energized tourge the pinion gear toward the meshing engagement. The current flowthrough the solenoid windings during these periods will be abnormallyhigh and may ultimately cause the solenoid coil Winding to becomeoverheated. This overheatingof the solenoid will ultimately result in ashort which may result in failure of the entire starting system.

It is an object, therefore, of the present invention to prevent theoverheating and resulting shorting of the solenoid in an automaticstarting system for internal combustion engines.

In carrying out the above object, it is another object of the presentinvention to prevent overheating of the solenoid in an automaticstarting motor apparatus for an internal combustion engine and to causea recycling of the starting motor circuit in event tooth end abutmentoccurs between the pinion gear of the starting motor drive and the ringgear of the engine to be cranked.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings wherein pre- United States Patent ferred embodiments of thepresent invention are clearly shown.

In the drawings:

The single figure illustrates an automatic starting motor systemincorporating the features of the present invention.

In the drawing, the starting motor for the internal combustion engine,not shown, includes; a starting motor 20, a starter drive 22, a startermotor solenoid 24, a storage battery 26 and a means for controlling theenergization of the starting motor solenoid 22 and the starting motor20.

The starting motor 20 is of the conventional type and the starter drivemay also be of the conventional type and may include a sprag or rollertype clutch 27 as, for example, as disclosed in application, Serial No.558,468, filed January 11, 1956, and assigned to the assignee of thepresent invention.

The solenoid 24 is provided with an outer casing 28 which, in practice,is usually attached to the frame of the starting motor. The casing 28encloses a pair of solenoid windings 30 and 32, a solenoid plunger 34, amagnetic pole piece 36 and a movable contact 38 which is arranged toengage the stationary contacts 40 and 41. The solenoid plunger 34 issuitably connected through a link 42 and a lever 44 with the starterdrive 22. The contact 40 is connected directly to the battery 26. Thecontact 41 is connected through a lead 46, to the field 48 of thestarting motor 20, and the armature of the starting motor, not shown, toground 50, from whence the circuit is complete to the ground 50 of thebattery. Winding 30 of the solenoid is formed of relatively fine wirewhich has one of its ends connected directly to ground 50 and the otherend connected through a lead 52 to a circuit which will be laterdescribed. Winding 32, which is formed of heavier wire, has one of itsends connected to lead 52 and its other end connected to the terminalfor contact 41. From the above, it is apparent that when current issupplied from the battery through a means which will be later described,to lead 52, current will flow through both windings 30 and 32. Thecurrent through winding 30 will be directly connected to ground 50 andthe current flow through winding 32 will pass from the lower terminal 41through lead 46, field 48 and the armature of starting motor to ground50. When current flows through these windings, the magnetic attractionset up in pole piece 36 will cause the solenoid plunger to move to theright, thereby moving the starter drive 22 so that the pinion 54 ismoved toward the ring gear 56 which is con nected to the engine to bestarted. If there is no abutment between the pinion gear 54 and ringgear 56, the teeth of the pinion gear will pass into engagement with thering gear. When this occurs, the plunger 34 will have moved sufficientlyto the right to cause the contacts 38 to engage contacts 40 and 41 andcomplete the circuit between the battery and the starting motor so thatthe motor will become energized. Also, when the contact 38 closes thecircuit through contacts 40 and 41, the winding 32 will be shorted outof the circuit so that the winding 30 will act as a hold-in winding tomaintain the plunger in the attracted position. When the starting motoris energized, it will rotate the shaft 58 which will cause the piniongear to be rotated to supply the cranking torque to the ring gear 56 ofthe engine.

The generating system which is used to charge the battery 26 forms apart of the control means for the starting system according to thepresent invention. In the embodiment shown, the generator 60 has oneoutput lead 61 connected to ground 50. The other output lead 62 isconnected through a junction 63 with the generator terminal 64 of aconventional current and voltage switch and regulator as used in presentday automotive vehicles; The regulator 65 has an internal circuit thatis prefer "non/"described.

The s'olenoid rcla'y 78'has ahactuating coil 34 mass "on a magnetic core'86 "which will attract thefiirni'a 88 andcauseehgagcmentbetween thecontacts 9 Whenever the coil 84 'is energized. The contact z carried onthe armature 88 and is connected in th the circuit breaker 76 with lead52. The contact 'cfinnectcdth'roughalead 94 and lead 74 with the/battery26 One endof the'actuating coil"84 of the'relay 781s connected thr'ougha lead 96 with the junction63. The other end ofthe coil 8-1 isconnectcdthrough the 'va'cuiiin switch 80 and the control switch 82 tolead '74'to battery Theswitch 82 is the main control switch and maybearranged to be either manually closed or closed automasonry by somesuitablemeans was to be responsive to "an 'outsidc'event as foran'example a failure in power which would require that'the stationaryengine be started to supply emergency :electric'c'urrent to a system.The switch Sil'is preferably a pressure type switch which are *wellknown which 'rnay be either connected to the oil -rircssure 'systein ofthe engine which is to be started or to the'engine'vacinirn. In eithercase the switch 80 is arranged so the contacts are normally closed whenthe engine is inoperative and will open after the 'oil "pressure of theengine or the engine vacuum reaches a "predetermined value at which timethe engine is selfoperative. This type of switch is also well known andin the particular embodiment shown the switch comprises a fluid motor80:: containing the usual flexible diaphragm which is moved leftwardlywhen a predetermined vacuum pressure exists within chamber 8%. Thediaphragm operates switch contacts 80c which are normally held closed by'a spring 8 nd until the spring is overcome by vacuum in chamber 89b.

From tl1 ea b ve 'it is apparentthat when switch 82 and switch 80 areclosed, current will flow from the battery 26 through lead 74 to theactuating coil 84, lead 96, junction 63, lead 62 where it will begrounded through the gener'ator-60 at ground 50. The currentflow'thr'ough coil 84 will eausethe armature to move and close con-'ta'cts '90 and 92. When, however, the engine becomes self operative tocause the generator to produce a current and voltage, the "voltage ofthe generator 60 will oppose 'the'volt'a'ge of the battery and cause thevoltage and current flow to the actuating coil 84 to become practically"zero. W henthis occurs, the actuating can will an be energizedsufii'e'iently to "attract armature 8'8 and continue the closure ofcontacts 99 and 92. This ar rangeinent provides -'a 's'afety feature to'cause thcopeni'n'g or contacts Q and 92 when the prime mover isselfoperative. I g

e "ch 76 may be of any suitable. type which is current responsive andmay be of the type disclosed in US. Patent 2,699,161. This switch is ofthe hot Wife 9 and will cause openin of the contacts 7611 after apredetermined amount "or current has passed through hot wire 76b for apredetermined time. This switch is "also adapted to cause reclo'sure ofthe contacts 76a of.

circuit breaker 76 after the current flow therethrough has 'ee ed for apredet rmined time. The hot wire 76b of t e circuit breaker 76 ispreferably designed so that a prolonged 'c'trnestnow through bothwindings 30 and '32 of the solenoid 24 \villfc'iuse the circuit breaker76 t6 u't neither the st state valuecf current i c ,r .,,l.-A. 7,through winding 30 nor the instantaneous surge of curl r 4 rent throughwindings 30 and 32 will cause opening of the circuit breaker 76. Theswitch 76 includes a conducting frame 760 which is pivoted at 76d. Aspring 76:: constantly biases the frame 760 in a clockwise direction andtoward an insulated stop. One of the contacts 76:: is connected with oneside of armature 88 while the other contact is electrically connected toone side of hot Wire 76b and through a spring arm 76 to frame 76c. Theframe 76c 'is electrically connected with lead 52. The hot'wire 76b isformed of any suitable wire that clongates upon'heating due to thepassage of a current therethrough and which contracts upon "cooling.Thus, when contacts 76a are closed, current flows through hot wire 76band through frame 760, the hot wire being heated during this time' Theresistance of the hot wire and circuit through the frame 760 are soproportioned that upon prolonged current fiow through windings 3t) and32 the hot wire elongates sufficiently so that spring 76c moves theframe to a position to open contacts 76a. When the wire 76b cools, itcontracts and'once more closes contacts 76a. 7

With theabove circuit arrangement in mind, the oper ation thereof willnow be described. When switch 82. is closed, the coil winding 84 will beenergized to setup a magnetic attraction in core 86 to cause themovement of armature 88 to close the contacts 90'and 9 2. The

closure of contacts 90 and 92 will cause the circuit from the battery tothe armature 88 and circuit breaker 76 to be complete so that currentwill flow through lead 52 through both windings 30and 32 of the solenoid28. When current flows through windings 30 and 32, the plunger 34 willbe attracted to move'the pinion gear 54 toward the ring gear. If thereis no tooth abutment between the gear teeth on the pinion 54 and ringgear 56, the solenoid plunger will travel a suflicient'distance to theright to cause contact 38 to close the circuit between contacts 40 and41 so as to complete the circuit from the battery to the starting motor.This in mm will causethe winding 32 to be deenergized so that thecircuit breaker does not open the circuit to winding 30. When tooth endabutment occurs, the contact 38 is not moved sufliciently to engage thecontacts 40 and 41 and current will continue to how through bothwindings 30 and 32. This current flow will cause the hot wire of thecircuit breaker 76 to cause an opening of the contacts of circuitbreaker 76. When thejcontactls of circuit breaker 76.open the circuit toboth windings 30 and 32 will be broken and the solenoid 24 will bedeenergized in spite of the fact that the switch 82 is closed. After apredetermined period of time, the circuit breaker 76 will operate andreclose the circuit to windings 30 and 32 so the starter drive 22 isagain moved toward the ring gear. Should abutment again occur, then thecircuit breaker 76 will again open to repeat the cycle of deenergizingand energizing the coil windings 30 and 3:2 Arepetition of theabovecycles will cause starting motor and starter drive parts to finally movesufliciently so that the pinion gear is positioned to pass into meshingengagement with the ring gear. This will permit the starting motor to beenergized Jtocr an-k the'engine. After the engine is self operative, thecircuit to the actuating coil 84 will be opened or deenergized byftheaction or the switch or the output of generator 60 to cause dee'nergiza'tion of the starting motor and th starting motor solenoid asheretofore described.

What is claimed is as follows:

In a "starting system for an internal combustion engine having a ringgear that is adapted to mesh with a pinion; the combination comprising;a starting motor, a source of current for energizing said starting'motor', a starter drive including a pinion bodily movable into cranking engagement with the ring gear of said engine for transmitting torquebetween said motor and engine, a first electric switch connected betweensaid starting motor and said source of current for completing a circuitthere 5 between, a solenoid actuator including a first holding winding,:1 second winding and a movable plunger, means connecting said plungerwith said starter drive for moving said pinion into engagement with saidring gear when said first and second solenoid windings are energized,means connecting said plunger and switch for operating said switch to aclosed position only after said pinion has meshed with the ring gear, asecond electric switch connected between said current source and saidfirst and second solenoid windings for completing a circuittherebetween, means responsive to current flow of greater than apredetermined magnitude through said first and second solenoid windingsfor opening said second switch and for maintaining said second switch inan open position for a predetermined time interval, said second switchremaining closed at a value of current flow through said 3 windings thatis less than said predetermined magnitude,

means for automatically reclosing said second switch after saidpredetermined time interval to automatically References Cited in thefile of this patent UNITED STATES PATENTS 1,901,285 Christian Mar. 14,1935 2,197,726 Johnson Apr. 6, 1940 2,302,687 Dyer Nov. 24, 19422,602,144 B01168 July 1, 1952 2,654,035 Rowell Sept. 29, 1953 2,699,161Pees Jan. 11, 1955 15 2,716,895 Antonidis Sept. 6. 1955 FOREIGN PATENTS379,805 Great Britain Sept. 8, 1932

